Method oe fabricating- thermoelectric units



N. H. ADAMS METHOD OF' FABHICATING THERMOELECTRIC UNITS .-Feb. 22,1927.

Flnd March 31 1925 Psalms resize, isa?.

Nennen n; ADAMS, or scnnuncfianr, New Yoan, Assreiion'iro annessi. nascente 1 COMPANY, a consonancia or new Yoan.

' Mnrnon or raisncnrnve Tnnaiaonnncrmc nimes.V

Applicationv filed March 31, 1925.' Serial No. 19,732.

My invention relates to thermo-electric flat surfaces and near their edges4 as shown 55 units and more particularly to a-rnethod of at 3. Successive unlike inet-al sheets are then fabricatinga multi-unit thermopile. added" to the ,first two sheets and in' Itis an object of my invention to provide line welded as at 4 and' 5 to form. an. intei afmethod of fabricating a compact therinogral zig-zag strip of any number of elefpile-which lwill permit quantity production ments desired. When the' strip contains the 60 of `thcrmopiles at a niinirnumexpense. y desired number of elementsvit is compressed. 'Il Hitherto,tliermopiles have been constructandl cut along the dotted lines 6, transverse to y edand assembled in such a crude and laborithev line of Weld, to form a plurality of ther- 3 ous manner" as. to preclude -their manufacino-pile units. Any suitable insulation ture cna commercial scale. In the present means suchas mica or the like may then be '65 application as well as in my copending apinserted ybetween the *severalv metal plates .plicationy SerialNo. 19,733' filed'Marcli 3l, Comprising the 'thermo-piles as shown 8 1925, I have disclosed a type of thermopilc and 9 and the unit-s assembled 'around a. eengadapted-for use in operating small electrical tral heater 10-as shown in Fig. 4. apparatus, such as the space currentdevices In. the preferred f embodiment of my in- 70 usedin radiobroadcast reception. Fora device volition as shown in Fig. 6 the successiveunof this characterto bccoinea coniinercialposlike thermo-electric metalsheets are -as sibility'f'itis obviously not only necessary that Senibled and line Welded on their dat sur- 10 it-should becapable of quantity production, 'faces and along their edges to form a zigbut that the cost of production should be rel- Zag 'strip as' set forth in connection with 75 atively small. With the method of 'fabrica- Figs.' 2 and v3. The metal sheets forming 'tibn disclosed in thepresent application it is the zig-zag strip are then compressed and possible to cpnstruct at reasonable cost a cut alon lines 11 transverse to the line of i5 compact thermopile havinga relatively large l Welfl'to-rorin a series of thermopile units l2,

numberocouples and adapted for the purthe individual metal plates or members of ,.90

pose .above specied. the units beingr rectangular in shape. i Each i;The novel features of myinvcntion which unit is then placed in a clamp or jig while 'Ibelieve to be characteristic are set' forth a 'slotoij groove 13 is machined in the welded uiwith particularity inthe appended claims: portionot tlie unit, which comprises the My invention itself7 however, 'will best be junction to be'heated. These junctions will 235- f understood by reference to 'the following dehereinafter bp referred to as the hot .juneseriptiontalren in Iconnection with thev toltions. Additional slots or grcovesl/l and lowing drawing in which Figs. l. and 5 show l5 are machined in eachy lside of the vunit 5 -plan views of stacks of sheets of theiino-elecadjacent the' iiot junction to provide relatric metaland 'the lines onwhich the' metal tively small connecting portions between 'the 90 may be out; Fig.' 2` shows diagraniinatically' hot junctions of the pile and the main. body the manner in which the 'successive sheets portion of the pile. Mica onothe-r suitable ,re'etlfiii'ttild Fig. 3 is a perspective view ot'a insulation is theninserted between the `difii i0 portion of a completed .thermopile; Fig. 4c is Vferent elements of the pile as in Fig. 3 and a planview 'oi a plurality of tl'iernno-piles the units assembled with' their slotted or 95 'arranged 'about a central heating element; grooved portions in opposition so aste sub- Fig.' 6 is an exploded view ot a preferred stantially surround a central insulated form of thermo-electricgenerator; Fig. 7 is heater clein'e'nt'l which closely iitsl within se aperspective view of a portion ot a thermo- 'thev grooved portions. By assembling, line pile and cooling means therefor; Fig. 8 Welding and cutting the metal sheets as '16e shows aplan view of a'plurality ot sheets shownjit isA possible to quickly produce a' of thermo-electricmetal 4with. a line weld large quai'itit'y of thermopiles` with a4 'extending centrally and vlengthwise otthe minimum .expenditure of time and at a rela,-

o metal sheets. tively low cost. i I

, In carrying myunethod of fabrication into By the 'provision of aslot or groove in the 105 :eechsuperpose two shects,1 and 2, ot dis; end portion of the thermo iles which insimilar'rnetals such. as*nickel-chromium and etudes the `hot junctions, lo tain -a relativecopper-nickel and line weld them upon their .ly large heat receiving surface which sube as before.

ther io de with the heating element. Grooves l5, which are cut in the sides of the fion* .of heat toward thev cold ji|nciince, however, '-a thermo-.electric r operates at its liigliesteiliciency en the interna-l resistance 'of the. gonorr is substantially equal to' the resistance the enter-nal load circuit supplied hy the into-r. 'the extent of grooves i4 and l5 i iccessarily governed'hy a consideration of the total internal resistance of the thermo- 'oiles and of -the loadr to he' supplied'by the the 'thermopiies `Such an arrangement is shown in Fig. 7. In th'isfrei'etufo unlike metal sh cts are superposed and Welded cloni" lieir fiat surfaces and rnear their hinweise to the line of weld to form a. plul"rofiity Gili-shaped sections 1-9 Two V sections .are tiren superppsed sol that unlike metal nietes will he adjacent and in parallel relatif the raided portion of the second section. A

cooling fin 20, of copper or anysuitahle ine is then inserted between the free ends or. the two'parallel plates which will o'omprise a. cold fiunction of the thermopjile ,and

iin and plates line Welded vor vperni'ij united` in any, suitable manner. li-shfqoed 'sections and cooling he added to the lfirst two sections the desired number ci'4 elements is cond in the therniopile unit: The .units i clamped `as vhetero while grooves and in the sides olf` the thermo- Wit. the hot junctions. Mica or insulation is than inserted as before the individual members of r the .i6 .A

.lewe

lirica i, h of each. element :off a thei'niopile', are .finocrgiosed as in the preceding, cases.y A

mie 'weld is then inadecentrallyand lenig-tlA wise the sheets as indicated 1h22 and thc two ets are then cut alonfgfthe dotted line The *welded tf-shaped portions are4 thon :ansif'erse to die nnc oi weld to provide n pini:

tiaiiy surrounds and isjclosely 'Sassopiles adjacent tljicliot junctions, re

The sheetsA infotheu cutJY to each` other, andthe-,welded -por-' tion ci' one section will be 'directly above ined .in thc end including the hottd' therme-pil@ .f-:ections which are supcrposed successively to form thedesired number oi' sections in the thermopilo The welded portions comprise the hot juxijitions oi*I the thermopile to he f'abricated'f'lho cold junctions may hc united to form a zig:-4 zag strip, as Shown in Fig. 2, by means of a. line weld or it desired, the different sheets may hoelcctroplated, the pile placed inl a ji, `piwlssurc applied, and the. ends permanently unitcdhy placing the pile in 'a suitable hcated furnace. The free end'sor cold -juuctioi'is might also, Aif desired, lie permanently connected by electroplat-ing ,the cold junctions with a hrazing material such as silver Aor spelter and then applying-ii 50 heavy current to the cold junetionswherehy i. la resistance weld may-be obtained. `lVlfen the zig-zag strip has been formed grooves are machined in the end and sides offe'aoln section as in Fig. 6. It Will be parent that various methods of joining ,tliegfree ends or cold junctions may.A he employedl without departing from the scope'ofvniy 'invention set forth v'in the appended claims;-v

VVhat I claim asnew and desiretosec'ure by Letters Patent of the United States, is

l. The method of fabricating thermo-eleotric Aunits which comprises su rposin sheets of unlike metal, line wel g sai sheets and snbdividing said sheets transverse to the line of Weld.A i i '1 i 2. The :method ofahricatinga thermoelectric unit which com rises superposing two sheets of unlike metall, linewelding-the sheets and cutting a slot in the 'Weldedportion of said sheets. I -y y 3. The method of' fabricating a' thermoeleetric unit which comprises assembling and line :Welding successive' unlike sheets o metal to form azig-zafr strip..4

i 4. The method of iabrieatingo thermm" electric unit which comprises 'assembling and line Woldingsucoessive unlike slieets of metal tojorn innig-zag (strip and cutting the strip-tmnsverse yto the line ofweld."

,5. The method of fabricating a thermoelectric unit which comprises assemblin and line Welding successiye unlike sheets o mettiti to form a zig-zag strip and euttingthe stri@ transverse vto the line ofweld to pro- Vide a. plurality of units and `cutting a slot in one side of one ofsaid units. f

6. The method of fabricating a thermo elect-ric unit which. comprises assemblili and line .Weldingsuocessi've vunlike sheets o- 15 metal 'to form a zig-zag stri cutting the strip transverse to the line ov Weld to vprovide. a plurality ol unitsandeutting a. slot in a yielded portion of a'unit.. L 7, The method of fabricating a tl'iern'io-v electric unit which lcomprises vassembling and ,line welding,rv successive unlike sheets of nxctzil to :forni a zigzag' strip,y cutting'the strip transverse to4 the' .linel of Welding to provi iza plurality of units and cutting a l slot in a Welded portion of a unit and another slot in one side of said unit adjacent said irst slot. 1

8. The method of fabricating a thermoelectric device which comprises assembling and. line Welding successive sheets of vunlike metal to form a zig-zag strip, cutting said strip transverse to said line of weld to provide a plurality of units and assembling -said units about an interposed heaten 9. The method of fabricating a thermoelectric device which comprises assembling and Welding successive sheets of unlike metal to form a zig-zag strip, cutting said strip to provide a plurality of units each unit including a plurality of hot junctions, cutting a slot in that portion of each unit including the hot junctions and assembling said units with their slotted portions in opposition.

l0. The method of fabricating a thermoelectric unit which comprises uniting a plurality of unlike metal plates to for-m a thermopile including a. plurality of hot junctions, and forming a slot in that portion of the thermopile includin the hot junctions.

11. The method of fa ricating a thermoelectric unit which comprises uniting a plurality of unlike metal'plates to form a thermoplle including a plurality of hot junctions, cutting a slot in that portion of the thermopile including the hot junctions and cutting another slot in the thcrmopile adjacent the hot junctions.

12. The method of fabricating a thermoelectric unit which comprises uniting a plurality of unlike metal plates to form a thermopile including a plurality of hot junctions, cutting -a slot in that portion of the thermopile comprising the' hot junctions and inserting a heater element in said slot.

In Witness whereof, I have hereunto set my hand this 30th day of March '1925.

NATHAN H. moans. 

